[Crm-sig] Money, money, money...

[Dan Matei]

Dear all

I have to state a "simple" fact: "The object X is purchased with Y euro."

I found the 2011 discussion between Vladimir Alexiev and Stephen Stead on this 
topic:
http://lists.ics.forth.gr/pipermail/crm-sig/2011-November/001693.html

I'm not quite happy with their conclusion :-(

Two issues:

A.      The relationship between the purchasing event and the money paid

I think that the natural relationship between the crm:E8_Acquisition and the 
amount paid (Y) is crm:P16_used_specific_object.

[P16 SN: This property describes the use of material or immaterial things in a 
way essential to the performance or the outcome of an E7 Activity.]

The money is "essential to the performance" of the acquisition, no ? :-)


B.      Which is the right class of the "money" ?

B.1. The amount is a crm: E72_Legal_Object, right ?

[E72 SN: This class comprises those material or immaterial items to which 
instances of E30 Right, such as the right of ownership or use, can be 
applied.]

Rights apply to money, right ?

So, my (first) solution is:

[
    {
        "@id": "#X",
        "@type": "crm:E22_Man-Made_Object",
        "statement": {
            "@id": "#s1",
            "predicate": "crm:P24i_changed_ownership_through",
            "object": "#purchase"
        }
    },
    {
        "@id": "#purchase",
        "@type": "crm:E8_Acquisition",
        "statement": {
            "@id": "#s2",
            "predicate": "crm:P16_used_specific_object",
            "predicateQualifier": "#amountPaid",
            "object": "#price"
        }
    },
    {
        "@id": "#price",
        "@type": "crm:E72_Legal_Object",
        "statement": [
            {
                "@id": "#s3",
                "predicate": "crm:P2_has_type",
                "object": "#currency"
            },
            {
                "@id": "#s4",
                "predicate": "crm:P43_has_dimension",
                "object": "#amount"
            }
        ]
    },
    {
        "@id": "#amount",
        "@type": "crm:E54_Dimension",
        "statement": [
            {
                "@id": "#s5",
                "predicate": "crm:P2_has_type",
                "object": "#sum"
            },
            {
                "@id": "#s6",
                "predicate": "crm:P90_has_value",
                "object": {
                    "@value": "Y",
                    "@type": "xsd:integer"
                }
            },
            {
                "@id": "#s7",
                "predicate": "crm:P91_has_unit",
                "object": "#euro"
            }
        ]
    }
]

A bit long... And the entity #price do not tells much.


B.2. An amount of money is not an instance of crm: E54_Dimension ?

[E54 SN: An instance of E54 Dimension represents the true quantity, independent 
from its numerical approximation, e.g. in inches or in cm.]

A sum of money is not "a true quantity" ? I'm inclined to the affirmative. So, 
if I understand correctly the E54, I could use a double instantiation and 
shorten a bit my solution:

[
    {
        "@id": "#X",
        "@type": "crm:E22_Man-Made_Object",
        "statement": {
            "@id": "#s1",
            "predicate": "crm:P24i_changed_ownership_through",
            "object": "#purchase"
        }
    },
    {
        "@id": "#purchase",
        "@type": "crm:E8_Acquisition",
        "statement": {
            "@id": "#s2",
            "predicate": "crm:P16_used_specific_object",
            "predicateQualifier": "#amountPaid",
            "object": "#price"
        }
    },
    {
        "@id": "#price",
        "@type": [
            "crm:E72_Legal_Object",
            "crm:E54_Dimension"
        ],
        "statement": [
            {
                "@id": "#s3",
                "predicate": "crm:P2_has_type",
                "object": [
                    "#currency",
                    "#sum"
                ]
            },
            {
                "@id": "#s4",
                "predicate": "crm:P90_has_value",
                "object": {
                    "@value": "Y",
                    "@type": "xsd:integer"
                }
            },
            {
                "@id": "#s5",
                "predicate": "crm:P91_has_unit",
                "object": "#euro"
            }
        ]
    }
]

I.e. the amount of money is in the same time an instance of E72 AND E54.

Is that legitimate ?

Dan